2009

TIP Some sky models neglect the influence of bounce light from the ground,
assuming only the sky is illuminating the scene. To compare the output of mr Sky
with, for example, the IES Sky model, one must therefore set Ground Color to
black.
After Dark group
Night Color The minimum color of the sky: The sky will never become darker
than this value. It can be useful for adding things like moon, stars, high-altitude
cirrus clouds that remain lit long after sunset, etc. As the sun sets and the sky
darkens, the contribution from Night Color is unaffected and remains as the
base light level.
To apply a map or shader to this parameter, click the None button.
Non-Physical Tuning group
Red/Blue Tint Provides artistic control over the redness of the sky light. The
default value of 0.0 is the physically correct value (calculated for a 6500K
whitepoint), but can be changed with this parameter, which ranges from -1.0
(extremely blue) to 1.0 (extremely red).
To apply a map or shader to this parameter, click the None button.
Saturation Provides artistic control over saturation of the sky light. The default
value of 1.0 is the physically calculated saturation level. Possible values range
from 0.0 (black and white) to 2.0 (extremely high saturation).
To apply a map or shader to this parameter, click the None button.
Aerial Perspective group
NOTE This parameter is for advanced users, and functions only when you use mr
Physical Sky is used as a lens shader or volume shader. When used as a lens shader,
the aerial perspective “mist” applies to primary rays only; it doesn't appear in
reflections. When used as a volume shader, it applies to the entire scene and every
ray in it, including reflections and refraction.
Visibility Distance Aerial Perspective is a term used by painters to convey
how distant objects are perceived as hazier and tinted towards the blue end
of the spectrum. mr Sky emulates this with the Visibilty Distance parameter.
When nonzero, it defines the “10% distance”, that is, the distance at which
approximately 10% of haze is visible at a Haze level of 0.0.
Sunlight and Daylight Systems | 5185